Amsonia plant named ‘Starstruck’

ABSTRACT

A new and distinct  Amsonia  plant named ‘Starstruck’ characterized by winter-hardy, compact, densely-stemmed, clean habit with oblanceolate, medium-green foliage that goes dormant in the winter; single, periwinkle-blue, star-shaped flowers on medium-tall dark purple scapes flowering beginning about early-May and effective for about four weeks. The new plant is useful in the landscape as a specimen or en masse and also as a cut flower.

Botanical classification: Amsonia hybrid.

Variety denomination: ‘Starstruck’.

STATEMENT REGARDING PRIOR DISCLOSURES UNDER 37 CFR 1.77(B)(6)

The first non-enabling disclosure of the claimed plant, in the form of awebsite to the public and email release to customers, was made byWalters Gardens, Inc. on Feb. 1, 2019. Since then, Walters Gardens, Inc.used photographs and descriptions of the new plant in their “WaltersGardens 19-20 Catalog” released on May 29, 2019 and sold the firstplants on Jul. 8, 2019. Walters Gardens, Inc. obtained the new plant andinformation about the new plant directly from the inventor. No plants ofAmsonia ‘Starstruck’ have been sold, in this country or anywhere in theworld, nor has any disclosure of the new plant been made more than oneyear prior the filing date of this application, and such sale ordisclosure within one year was either derived directly or indirectlyfrom the inventor.

BACKGROUND AND ORIGIN OF THE PLANT

The present invention relates to a new and distinct Blue Star plant,Amsonia ‘Starstruck’ hereinafter also referred to as the new plant orjust the cultivar name, ‘Starstruck’. Amsonia ‘Starstruck’ washybridized by the inventor in the spring of 2011 in a trial field at awholesale perennial nursery in Zeeland, Mich., USA. The new plantoriginated from a breeding program conducted by the inventor with thespecific intention to improve the garden worthiness, expand colorregimens and increase flowering period which were some of the criteriaof further trials in the trial beds at the same nursery in Zeeland,Mich. The female or seed parent was a propriety unnamed selection ofAmsonia rigida (not patented) and the male or pollen parent was apropriety unnamed selection of Amsonia tabernaemontana (not patented).Seeds from the cross were collected on Oct. 6, 2011. The new plant wasselected as a single seedling from this cross, and after confidentialevaluations in a trial bed beginning in 2012 in Zeeland, Mich. the newplant resulting from a single seedling was assigned the breeder code11-70-01 through the remaining trial period prior to assigning acultivar name.

The new plant has been asexually propagated by shoot tip cuttings at thesame wholesale nursery in Zeeland, Mich. since 2012 with all resultantasexually propagated plants having retained all the same unique traitsas the original plant. Amsonia ‘Starstruck’ has proven to be stable andreproduces true to type in successive generations of asexualreproduction.

The most similar known Blue Star cultivar is ‘Storm Cloud’ (notpatented). ‘Storm Cloud’ is taller in habit, with darker purple in thestems, wider foliage with more significant silver veining, with earlierand longer branching, not as compact flowering and a flowering seasonthat begins one to two weeks earlier. The female parent is taller with amore open habit, broader foliage, and has soft blue flowers on darkerstems. The male parent is slightly taller with wider foliage. The newplant can also be compared with ‘Blue Ice’ (not patented) which has ashorter more spreading habit compared with the new plant.

Amsonia ‘Starstruck’ differs from all other Blue Star plants known tothe applicant, by the combination of the following traits:

-   -   1. Periwinkle-blue star-shaped flowers in clusters near the end        of the stems;    -   2. Flowering above the foliage in mid-spring on dense panicles        for about three to four weeks.    -   3. Winter-hardy to USDA zone 4, compact, densely-stemmed, clean,        medium-green foliage that goes dormant in the winter;    -   4. Foliage and stems have white latex sap making the plants        undesirable to deer and rabbits.

BRIEF DESCRIPTION OF THE DRAWINGS

The photograph of the new plant demonstrates the overall appearance ofthe plant, including the unique traits. The colors are as accurate asreasonably possible with color reproductions. Ambient light spectrum,temperature, source and direction may cause the appearance of minorvariation in color.

FIG. 1 shows an eight-year-old plant in peak flower during mid-summer ina full-sun trial garden in Zeeland, Mich.

FIG. 2 shows a close-up of the flower and buds.

DETAILED BOTANICAL DESCRIPTION

The following descriptions and color references are based on the 2015edition of The Royal Horticultural Society Colour Chart except wherecommon dictionary terms are used. The new plant, Amsonia ‘Starstruck’,has not been observed under all possible environments. The phenotype mayvary slightly with different environmental conditions, such astemperature, light, fertility, moisture and maturity levels, but withoutany change in the genotype. The following observations and sizedescriptions are of an eight-year-old plant in a sunny research gardenbed in Zeeland, Mich. with and supplemental water and fertilizer.

-   Botanical classification: Amsonia hybrid;-   Parentage: female or seed parent is a proprietary unreleased    selection of A. rigida; male or pollen parent is a proprietary    unreleased selection of A. tabernaemontana;-   Propagation: Division of the rhizome and shoot tip cuttings;-   Growth rate: Moderate;-   Crop time: About 15 to 20 weeks starting in early summer to grow a    2.5 cm plug to a flowering 3.8 liter container after vernalization;-   Plant shape and habit: Winter-hardy herbaceous perennial with    numerous stems with dark green foliage in a dense mound;-   Plant size: Foliage height about 74 cm tall from soil line to the    top of the flowers and about 107 cm wide about 25 cm above the soil;-   Rooting habit: Primary roots thick, fleshy and seldom branched, to    30 cm long and 5.0 mm thick, color between RHS 165 B and RHS 165C;    depending on soil type; secondary roots fibrous, to about 6 cm long    and 1.0 mm diameter, color between RHS 158D and RHS 165D depending    on soil type;-   Leaves: Oblanceolate; sessile; alternate; entire; glabrous and    glaucous both abaxial and adaxial; apex acute, base cuneate; about    24 leaves per stem; to about 5.5 cm long and 15.0 mm across near    middle; attitude mostly outright;-   Leaf color: Expanding adaxial nearest RHS 146A with tinting of    nearest RHS N187A and abaxial nearest RHS 146B with tinting nearest    RHS N187A; mature adaxial nearest a blend of RHS NN137B and RHS    137A, and abaxial nearest RHS 146A;-   Veins: Pinnate; adaxial puberulent; abaxial glabrous;-   Vein color: Mature and expanding adaxial midrib between RHS 151D and    RHS145C secondary adaxial veins nearest RHS 146D; mature and    expanding abaxial midrib RHS 146C and secondary veins nearest RHS    146D;-   Stem: Cylindrical; glabrous; lustrous; to 46 cm tall and 6.0 mm    diameter at base; with about 19 nodes per stems below flowering    branches; average internode length about 2.4 cm;-   Stem color: As emerging with leaves still tight nearest a blend    between RHS 137A and RHS N187A; at flowering time lower portion    nearest RHS 137B and upper portion a blend between RHS N187A and RHS    NN137B;-   Inflorescence: Branched panicle densely flowered in terminal    portion; flowering about 8.0 cm across and 7.0 cm tall; about 30 to    50 flowers per panicle; inflorescences remain effective beginning    early-May repeating for approximately four weeks in Zeeland, Mich.;-   Flowers: Rotate, salverform; single; perfect; complete;    actinomorphic; upward and outwardly facing; about 14.0 mm across in    face and 8.0 mm tall, corolla tube about 7.0 mm long and 2.0 mm    diameter; corona in center eye, about 4.0 mm across and 1.0 mm tall;    individually lasting for about five to seven days; Flower fragrance:    none detected;-   Buds one to two days prior to opening: Ellipsoidal with rounded apex    and base; about 9.0 mm long and about 2.0 mm in diameter at widest    point with near middle;-   Bud color one day from opening: Nearest RHS 91B;-   Petals: Five; made up of fused corolla tube and perpendicular    flattened limb; limb portion lanceolate, separate, not overlapping,    with acute apex; limb portion about 6.0 mm long and 2.0 mm across;    corolla tube puberulent in abaxial and distal 3.0 mm protruding    above face in corona; also puberulent adaxial in the 2.0 mm below    face, glabrous elsewhere;-   Petal color: Adaxial face between RHS 91B and RHS 91C, with 1.0 mm    center eye nearest RHS 96C; abaxial face between RHS 92C and RHS    92D; adaxial corolla tube distally nearest RHS 92C, center portion    nearest RHS 138D and basal 2.0 mm nearest RHS 92C; abaxial corolla    tube nearest RHS 96C distally, basal 4.0 mm between RHS 92B and RHS    92C, center portion between RHS 145A and RHS 146D; corona nearest    RHS 97D; hairs nearest RHS NN155D;-   Pedicel: Cylindrical; glabrous; lustrous; average about 3.0 mm long    and 0.5 mm diameter; upright and outright;-   Pedicel color: Nearest RHS 146A;-   Peduncle: Cylindrical; glabrous; lustrous; typically one per    division; just below flowering portion about 5.0 mm diameter at    base, average 7.0 cm tall; extending above foliage; branches to    about 3.5 cm long and 1.5 mm diameter;-   Peduncle color: Between RHS 146D and RHS 144A proximally and    strongly maculate distally to nearest RHS N187A;-   Gynoecium: Single; about 6.0 mm long;    -   -   Style.—Single; cylindrical; glabrous; about 3.5 mm long, 0.3            mm diameter; color nearest RHS NN155D.        -   Stigma.—Globose; about 0.5 mm across; color nearest RHS            144A.        -   Ovary.—Superior; globose; about 1.3 mm long and 1.0 mm;            color nearest RHS 138A.-   Androecium: Five; adnate to inner corolla;    -   -   Filaments.—Five; adnate to inner corolla and extending about            6.0 mm to 7.0 mm above corolla base, and free in distal 1.0            mm; about 0.2 mm in diameter; color nearest RHS NN155D.        -   Anthers.—Oblong; basifixed, longitudinal; about 1.0 mm long            and 0.5 mm wide; color closest to RHS N187A.        -   Pollen.—Abundant; color nearest RHS 158B.-   Fruit: Slender; upright; non-fleshy; dried follicle; singled seeded    in diameter; dehiscing along a longitudinal spiral; to about 10.0 cm    long and 3.0 mm in diameter; color while maturing nearest RHS 138B    and at dehiscence nearest RHS 164C;-   Seed: Up to about 10 per follicle; cylindrical; apices and bases    either truncate or angular; asperous; about 9.0 mm long, about 2.0    mm wide and about 1.0 mm thick; color nearest RHS 200D;-   Disease and pest resistance and tolerance: ‘Starstruck’ shows    typical Blue Star resistant to deer and rabbits but has not shown    resistance to diseases and pests beyond that common for Blue Star    plants. The plant grows best and shows best coloration with    full-sun, plenty of moisture, adequate drainage, but is able to    tolerate some drought when mature and direct sun without leaf burn    when provided sufficient water.

Hardiness at least from USDA zone 4 through 9. The new plant is usefulfor landscaping en masse, as a single specimen or small groups, as acontainer plant or as a cut flower.

The invention claimed is:
 1. A new and distinct ornamental Blue Star,Amsonia plant named ‘Startstruck’ as herein described and illustrated.